我跟着http://railscasts.com/episodes/17-habtm-checkboxes-revised?view=asciicast教程通过关系成立的has_many,当我尝试从一个模型获取信息它的工作原理,但不是从其他只做我的has_many之一。为什么虽然型号工作
我可以通过@product.category_ids
和@product.categories
从产品型号访问类别信息,但反过来却不是这样。我无法从类别模型中访问产品信息。使用@category.product_ids
或@category.products
给我的错误NoMethodError: undefined method 'product_ids' for #<Category:0x007fa70d430e98>
Product.rb
class Product < ActiveRecord::Base
attr_accessible :category_ids
has_many :categorizations
has_many :categories, through: :categorizations
accepts_nested_attributes_for :categorizations, :allow_destroy => true
end
Category.rb
class Category < ActiveRecord::Base
attr_accessible :product_ids
has_many :categorizations
has_many :products, through: :categorizations
end
- 编辑 -
Schema.rb
ActiveRecord::Schema.define(:version => 20130926192205) do
create_table "categories", :force => true do |t|
t.string "name"
t.datetime "created_at", :null => false
t.datetime "updated_at", :null => false
end
create_table "products", :force => true do |t|
t.string "name"
t.datetime "created_at", :null => false
t.datetime "updated_at", :null => false
end
create_table "categorization", :force => true do |t|
t.integer "product_id"
t.integer "category_id"
t.datetime "created_at", :null => false
t.datetime "updated_at", :null => false
end
add_index "categorization", ["product_id", "category_id"], :name => "index_categorization_on_product_id_and_category_id", :unique => true
add_index "categorization", ["product_id"], :name => "index_categorization_on_product_id"
add_index "categorization", ["category_id"], :name => "index_categorization_on_category_id"
end
什么是您的架构是什么样子? – Oliver
在上面添加了它。 –